How to Make Minor Corvette Sheet-Molded Composite Repairs - Skin Deep

Demystifying minor SMC Repairs

Far be it from us to counsel restraint when it comes to piloting one's Corvette, particularly if it's a late-model edition kitted up with all the mod cons that make everyday driving such a pleasure. That said, there comes a point at which even the most dedicated Vette votary has to wonder if perhaps it's time to relegate his (or her) pride and joy to weekend duty.

Consider the case of Mark Dickey's "Orange Krush" '01 Z06, a dazzling, LSX454-powered daily driver that graced the cover of our Aug. '05 issue.
In the years since its magazine debut, the car has been a veritable lodestone for automotive misfortune, suffering a fascia-defacing runinwith an armadillo in the Arizona desert, a high-speed rear-ending by a furniture truck in Tampa traffic, and, most recently, a vicious side-swiping in the parking lot of a local shopping mall. If Corvettes were stuntmen, Dickey's would be Super Dave Osborne.

Fortunately our Mr. Dickey is a stalwart fellow with an excellent insurance policy, and in the first two of the aforementioned instances, he was able to have the car repaired to full pre-wreck salubrity. The side-swipe fix, meanwhile, is currently underway, which brings us (in admittedly roundabout fashion) to the topic of this how-to article.

While much of the mall-crash damage will be rectified by simply replacing the affected panels, some of these items have been discontinued by GM and will therefore need to be mended with an SMC (sheet-molded composite) repair agent. Dickey entrusted this work to the Corvette pros at AntiVenom in Seffner, Florida—the same folks who handled the mechanical portion of Orange Krush's initial build way back in 2007.

Knowing that minor SMC repairs tend to be well within the capabilities of the average DIYer, we tagged along, camera and notepad in hand, to document the process. Let's take a closer look at how the job unfolded.

Note: The repair method detailed here is only applicable to '82-up Corvettes. Earlier models, which were built using glass-reinforced plastic, or GRP, require a different procedure.

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1. For this job, we'll be using a 3M SMC-repair kit obtained from Summit Racing (Summit PN tRM-8243). the kit includes the two-part adhesive itself, along with a pair of application nozzles.

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2. AntiVenom's Greg Lovell starts the job by grinding the damaged areas down to a depth of approximately a quarter of an inch using a 3M Roloc disc. (Note: If you're following along at home, be sure to use wear an approved protective mask during any portion of the job that requires sanding.)

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3. The resulting panel should look something like this.

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4. With the top surface completed, Lovell repeats the process on the back side of each crack. Here, he's using 80-grit sandpaper to treat a particularly hard-to-reach area.

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5. As above, so below.

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6. With the initial sanding work done, Lovell blows away any residual dust with compressed air...

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7. ...then thoroughly cleans the surrounding painted area using greaseand-wax remover. If you're doing this work yourself, be sure to avoid getting any of the removing agent on the exposed fiberglass.

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8. The next step involves evening up and securing the fractured surfaces to ensure a nice, flat repair. any method will do, as this creative pen-and-Vise-Grip configuration amply illustrates.

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9. After installing one of the two included nozzles on the tube of two-part adhesive, Lovell uses a purposespecific 3M gun (Summit PN tRM-8571) to apply a moderate amount of compound to the first damaged area.

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10. In this photo, you can see how our makeshift brace forces the upper and lower portions of the panel firmly together at the crack.

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11. Immediately following the initial application, Lovell uses a rubber squeegee to smooth and flatten the adhesive over the affected area. you'll need to work fast here, as this material achieves a rock-hard consistency in just 50 seconds.

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12. As with the sanding, Lovell repeats the job on the rear side of the panel.

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13. The result is shown here. when you're done applying the adhesive, allow it to cure for at least an hour before moving on to the next step.

15. After smoothing out the area with the sanding disc, he finishes the filler-prep process by hand, using 80-grit sandpaper. the goal here is to leave a slight V-shaped concavity along the length of each crack (front and back); this will provide a good point of purchase for the filler.

MORE PHOTOS

1. For this job, we'll be using a 3M SMC-repair kit obtained from Summit Racing (Summit PN tRM-8243). the kit includes the two-part adhesive itself, along with a pair of application nozzles.

2. AntiVenom's Greg Lovell starts the job by grinding the damaged areas down to a depth of approximately a quarter of an inch using a 3M Roloc disc. (Note: If you're following along at home, be sure to use wear an approved protective mask during any portion of the job that requires sanding.)

3. The resulting panel should look something like this.

4. With the top surface completed, Lovell repeats the process on the back side of each crack. Here, he's using 80-grit sandpaper to treat a particularly hard-to-reach area.

5. As above, so below.

6. With the initial sanding work done, Lovell blows away any residual dust with compressed air...

7. ...then thoroughly cleans the surrounding painted area using greaseand-wax remover. If you're doing this work yourself, be sure to avoid getting any of the removing agent on the exposed fiberglass.

8. The next step involves evening up and securing the fractured surfaces to ensure a nice, flat repair. any method will do, as this creative pen-and-Vise-Grip configuration amply illustrates.

9. After installing one of the two included nozzles on the tube of two-part adhesive, Lovell uses a purposespecific 3M gun (Summit PN tRM-8571) to apply a moderate amount of compound to the first damaged area.

10. In this photo, you can see how our makeshift brace forces the upper and lower portions of the panel firmly together at the crack.

11. Immediately following the initial application, Lovell uses a rubber squeegee to smooth and flatten the adhesive over the affected area. you'll need to work fast here, as this material achieves a rock-hard consistency in just 50 seconds.

12. As with the sanding, Lovell repeats the job on the rear side of the panel.

13. The result is shown here. when you're done applying the adhesive, allow it to cure for at least an hour before moving on to the next step.

15. After smoothing out the area with the sanding disc, he finishes the filler-prep process by hand, using 80-grit sandpaper. the goal here is to leave a slight V-shaped concavity along the length of each crack (front and back); this will provide a good point of purchase for the filler.

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